indexVariability: Calculate 'variability' of a grid as defined by Slater (1977).
Description
Variability records a tendency for the responses to gravitate
towards both end of the gradings scale. (Slater, 1977, p.88).
Usage
indexVariability(x, min, max, digits = 2)
Arguments
min
Minimum grid scale value.
max
Maximum grdi scale value.
digits
Numeric. Number of digits to round to (default is
2).
References
Slater, P. (1977). The measurement of intrapersonal space
by Grid technique. London: Wiley.